This disclosure relates to multi-layer circuits. In particular, it relates to methods of making multi-layer circuits using a resin covered conductive layer comprising liquid crystalline polymer.
Circuits typically comprise a conductive circuit layer bonded or laminated to a dielectric layer. The conductive circuit layer is generally a conductive metal such as copper, and the dielectric layer generally comprises a polymer resin such as epoxy or polybutadiene. Depending on the selection of dielectric layer and its thickness, circuits can be either stiff or flexible.
Multi-layer circuits generally comprise at least one conductive circuit layer bonded to either another circuit or to a resin covered conductive layer, often referred to as a xe2x80x9ccap layerxe2x80x9d. More complex configurations are also possible, having two or more circuits and one or more resin covered conductive layers. While suitable for their intended purposes, the requirements for multi-layer circuits and high density, high performance applications are becoming ever more demanding with respect to density and environmental and electrical performance. Accordingly, there remains a need in the art for a multi-layer circuit comprising a resin covered conductive layer that can meet these needs.
An improved multi-layer circuit comprises a circuit and a resin covered conductive layer disposed on the circuit, wherein the resin comprises a liquid crystalline polymer resin laminated to the conductive layer. Use of such resin covered conductive layers results in multi-layer circuits having a combination of mechanical, electrical, and thermal properties better than those currently available.
The above discussed and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description and drawings.